Cessna citation has pressurization loss and FMS failure.

Attributes
ACN	476973
Time
Date	200006
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : ood.vortac
State Reference	PA
Altitude	msl single value : 37000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny.artcc
Operator	general aviation : personal
Make Model Name	Citation II S2/Bravo
Operating Under FAR Part	Part 91
Navigation In Use	other other vortac
Flight Phase	cruise : level
Route In Use	enroute airway : j42.airway
Flight Plan	IFR
Person 1
Affiliation	other
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 5900 flight time type : 500
ASRS Report	476973
Person 2
Affiliation	other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	faa : reviewed incident with flight crew other Other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

The incident occurred while on an instrument flight originating out of winston-salem, nc (int), and ending at boston, ma (bos). While in cruise flight at FL370, I noticed a hissing sound coming from around the main cabin door. I checked the cabin controller gauge and it indicated a climbing cabin pressure. I immediately donned my oxygen mask and advised the PIC/PF to do the same, and he did. At this time the rapid decompression checklist was begun. Prior to its completion, the pressure leak from around the cabin door increased to a very high level. At this point the PIC/PF initiated an emergency descent, during which the aircraft was turned off the airway. During the emergency descent and after completion of both rapid decompression and emergency checklist, the security of all the passenger was assured and that they all had the oxygen masks on and were receiving adequate oxygen. During the descent, attempts were made to notify ZNY of our intentions. While squawking 7700 transponder code, contact was established and ATC notified of our emergency. The PF leveled the aircraft at 10000 ft. I advised the PIC/PF at this time we should fly to the nearest suitable airport. The PIC/PF decided to continue to our original destination at 10000 ft or less and unpressurized. ATC was advised of our intentions to continue to bos and that the decompression emergency was over. ATC issued a new clearance and squawk code from 7700. While navigation to bdr VOR, it was noted that our FMS was malfunctioning with erroneous heading and distance information. We advised ATC that our FMS equipment had failed. We continued with VOR navigation. We were given an altitude of 9000 ft at which we descended to and I reminded the PIC/PF of our restr 250 KTS below 10000 ft, and the flight continued to bos with no further incident. Upon landing, we were advised by ground control to contact ZNY and telephone number. This we did expediently after our arrival at the terminal. I advised ZNY by phone what emergency we had, and what had taken place.

Original NASA ASRS Text

Title: CESSNA CITATION HAS PRESSURIZATION LOSS AND FMS FAILURE.

Narrative: THE INCIDENT OCCURRED WHILE ON AN INST FLT ORIGINATING OUT OF WINSTON-SALEM, NC (INT), AND ENDING AT BOSTON, MA (BOS). WHILE IN CRUISE FLT AT FL370, I NOTICED A HISSING SOUND COMING FROM AROUND THE MAIN CABIN DOOR. I CHKED THE CABIN CONTROLLER GAUGE AND IT INDICATED A CLBING CABIN PRESSURE. I IMMEDIATELY DONNED MY OXYGEN MASK AND ADVISED THE PIC/PF TO DO THE SAME, AND HE DID. AT THIS TIME THE RAPID DECOMPRESSION CHKLIST WAS BEGUN. PRIOR TO ITS COMPLETION, THE PRESSURE LEAK FROM AROUND THE CABIN DOOR INCREASED TO A VERY HIGH LEVEL. AT THIS POINT THE PIC/PF INITIATED AN EMER DSCNT, DURING WHICH THE ACFT WAS TURNED OFF THE AIRWAY. DURING THE EMER DSCNT AND AFTER COMPLETION OF BOTH RAPID DECOMPRESSION AND EMER CHKLIST, THE SECURITY OF ALL THE PAX WAS ASSURED AND THAT THEY ALL HAD THE OXYGEN MASKS ON AND WERE RECEIVING ADEQUATE OXYGEN. DURING THE DSCNT, ATTEMPTS WERE MADE TO NOTIFY ZNY OF OUR INTENTIONS. WHILE SQUAWKING 7700 XPONDER CODE, CONTACT WAS ESTABLISHED AND ATC NOTIFIED OF OUR EMER. THE PF LEVELED THE ACFT AT 10000 FT. I ADVISED THE PIC/PF AT THIS TIME WE SHOULD FLY TO THE NEAREST SUITABLE ARPT. THE PIC/PF DECIDED TO CONTINUE TO OUR ORIGINAL DEST AT 10000 FT OR LESS AND UNPRESSURIZED. ATC WAS ADVISED OF OUR INTENTIONS TO CONTINUE TO BOS AND THAT THE DECOMPRESSION EMER WAS OVER. ATC ISSUED A NEW CLRNC AND SQUAWK CODE FROM 7700. WHILE NAV TO BDR VOR, IT WAS NOTED THAT OUR FMS WAS MALFUNCTIONING WITH ERRONEOUS HDG AND DISTANCE INFO. WE ADVISED ATC THAT OUR FMS EQUIP HAD FAILED. WE CONTINUED WITH VOR NAV. WE WERE GIVEN AN ALT OF 9000 FT AT WHICH WE DSNDED TO AND I REMINDED THE PIC/PF OF OUR RESTR 250 KTS BELOW 10000 FT, AND THE FLT CONTINUED TO BOS WITH NO FURTHER INCIDENT. UPON LNDG, WE WERE ADVISED BY GND CTL TO CONTACT ZNY AND TELEPHONE NUMBER. THIS WE DID EXPEDIENTLY AFTER OUR ARR AT THE TERMINAL. I ADVISED ZNY BY PHONE WHAT EMER WE HAD, AND WHAT HAD TAKEN PLACE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.